Substrate processing method

1. A substrate processing method, the method comprising:

providing a substrate having an oxidized layer formed thereon;

replacing the oxidized layer with a fluorine-based layer;

exposing the fluorine-based layer to an oxidizing atmosphere, wherein the fluorine-based layer protects the substrate against oxidation by the oxidizing atmosphere; and

removing the fluorine-based layer from the substrate using a plasma process; wherein the substrate is maintained under vacuum conditions before removing the fluorine-based layer.

2. The method of claim 1 , wherein the replacing comprises

exposing the oxidized layer to a cleaning gas containing a) NH 3 and HF, or b) NF 3 and HF, wherein the exposing passivates the substrate with the fluorine-based layer.

3. The method of claim 1 , wherein the replacing comprises

removing the oxidized layer from the substrate; and

thereafter, passivating the substrate with the fluorine-based layer.

4. The method of claim 3 , wherein removing the oxidized layer comprises

exposing the oxidized layer to a cleaning gas containing a) NH 3 and HF, or b) NF 3 and HF; and

thereafter, heat-treating the substrate.

5. The method of claim 3 , wherein the passivating comprises

exposing the substrate to a fluorine-containing plasma.

6. The method of claim 5 , wherein the fluorine-containing plasma is generated using a microwave plasma source.

7. The method of claim 1 , wherein the oxidizing atmosphere contains air.

8. The method of claim 1 , wherein the removing includes exposing the fluorine-based layer to a plasma containing H 2 , N 2 , Ar, or NH 3 , or a combination of two or more thereof.

9. The method of claim 1 , wherein the substrate contains Si, SiGe, Ge, or a compound semiconductor.

10. A substrate processing method, the method comprising:

providing a substrate having an oxidized layer formed thereon;

replacing the oxidized layer with a fluorine-based layer;

exposing the fluorine-based layer to an oxidizing atmosphere, wherein the fluorine-based layer protects the substrate against oxidation by the oxidizing atmosphere;

removing the fluorine-based layer from the substrate using a plasma process;

following the removing, forming an oxygen-containing interface layer on the substrate; and

depositing a high-k film on the oxygen-containing interface layer.

11. The method of claim 10 , wherein forming an oxygen-containing interface layer on the substrate includes exposing the substrate to an oxygen-containing plasma containing O, O 3 , H 2 O, or a combination thereof.

12. The method of claim 11 , wherein the oxygen-containing plasma is generated using a microwave plasma source.

13. The method of claim 12 , wherein the substrate is maintained under vacuum conditions from before removing the fluorine-based layer to after depositing the high-k film.

14. A substrate processing method, the method comprising:

providing a Ge-containing substrate having an oxidized layer containing Ge formed thereon;

removing the oxidized layer from the Ge-containing substrate by an exposure to a cleaning gas containing a) NH 3 and HF, or b) NF 3 and HF, wherein the exposure to the cleaning gas further passivates the Ge-containing substrate with a fluorine-based layer;

exposing the fluorine-based layer to an oxidizing atmosphere, wherein the fluorine-based layer protects the Ge-containing substrate against oxidation by the oxidizing atmosphere;

removing the fluorine-based layer from the Ge-containing substrate using a microwave plasma process containing H 2 gas;

thereafter, forming an oxygen-containing interface layer on the Ge-containing substrate using a microwave plasma process; and

depositing a high-k film on the oxygen-containing interface layer, wherein the Ge-containing substrate is maintained under vacuum conditions from before removing the fluorine-based layer to after depositing the high-k film.

15. A substrate processing method, the method comprising:

providing a passivated substrate in a vacuum processing tool, the passivated substrate having a fluorine-based layer thereon that is effective for protecting the passivated substrate against oxidation by an oxidizing atmosphere;

removing the fluorine-based layer from the passivated substrate using a microwave plasma process in the vacuum processing tool, thereby forming a clean substrate; and

processing the clean substrate under vacuum conditions.

16. The method of claim 15 , wherein the passivated substrate contains Si, SiGe, Ge, or a compound semiconductor.

17. The method of claim 15 , wherein providing the passivated substrate includes

providing the substrate having an oxidized layer formed thereon; and

replacing the oxidized layer with the fluorine-based layer.

18. The method of claim 17 , wherein the replacing comprises

exposing the oxidized layer to a cleaning gas containing a) NH 3 and HF, or b) NF 3 and HF, wherein the exposing removes the oxidized layer and passivates the substrate with the fluorine-based layer.

19. The method of claim 18 , wherein the substrate is maintained under vacuum conditions from before removing the fluorine-based layer to after processing the clean substrate.

20. The method of claim 15 , wherein the passivated substrate contains a recessed feature and a metal contact in the recessed feature.

21. The method of claim 15 , wherein the processing comprises

following the removing, forming an oxygen-containing interface layer on the substrate; and

depositing a high-k film on the oxygen-containing interface layer.